用英文写一封投诉信

Dear sir/madam,
Hi,this is xx. I've bought a XX(商品) for XX(价格) dollar from XX(商场名称) shopping mall on XX/XX/XXXX(日期).Today when I want to use it to XX, I was suprised found that it doesn't work at all.(这里可以加描述到底怎么坏的)I brought it because I need to use it and now your good is useless. This causes a lot of inconvient for me.I want to know what are you going to do about this, and when can you fix this problem.
I hope I can hear from you soon, or I would think about using the legal solutions.

Yours sincerely,
XX

To whom it may concern,
I'm writing to complain about the SQ200 I bought from your department store the other day. It worked very well the first months,however, when I used it later, I could neither send my friends messages nor take photos with my cellphone.

I think you will try to help me solve this problem.I have two options here, maybe you can take it as reference. First, I think I can change my phone to another one if possible.Second, maybe you should pay me refund because of the issue.

I hope you can figure out which measure to take wholeheartedly.Your cooperation will be highly appreciated.I'm looking forward to its solution.

A Letter of Complaint
Dear sir/madam,
Hello.This is Li Hua who bought a Nokia cell phone at your shopping mall on September 22nd,2010 at the price of 600 yuan.It worked well for the first three days.I liked it very much.But two days later,exactly on the sixth day,I was talking with my friend on it in the morning when suddenly I could not hear my friend on line and he could not hear me either.I held up and dialed again and again,but I could not reach the number.Just now I tried for another time,but failed .I believe that there must be something wrong with the cell phone.Now I am writing to tell you all.I would like you to change another one for me.Looking forward to your reply.
Regards

Yours
Li Hua

现在才看到你的问题。希望能帮到你